250ZR

Cheers for the response, I think i'm on my own lol I will however double and triple check the wire i have when i get home, i do know that the wire i am using at home doesn't draw enough power to light up the test lamp, (at least not during previous tests.) My wiring is quite similer except that my fuel pump is constantly hot and connected to pin 3 on your diagram and pin 4 grounds the pump to complete the circut. this is the way the origional RB20 red top was wired... (as my car is a Z31 200zr) flip side is it never used a relay... the ecu grounded all 12-13v and 11amps its self (no idea why they would do that but thats how it was from factory...) my current thought for a solution at the moment is to install a gas safety switch as its only on with a pulse signal generated from say the CAS or coil packs etc. however i am un-aware if i will still get the 5 second prime with this switch. (might just be dodgy and install a press button to manually prime my pump before start). if anyone has any other safe alternative ideas to make a fuel pump only run during engine operation I'm all ears thanks

Ok guys so its a bit of a copy and paste thread but i am just asking around and since i got pretty much this far with my RB25 Z31 200zr (250zr now) with the help of all your documentation on RB swaps. I'm hoping someone has come across this or has a some thoughts and theory on it. the problem i just can't rap my head around. I has just installed an RB25det out of an 95 r33 gtst into a Z31 and everythings completed bar the fuel pump. we've determined that the ecu and motor are actually series 2 items as the wiring has only 1 ign relay and 1 large white dash loom plug as apposed to the earlier models. when attempting to wire in the Z31 fuel pump to a relay controlled by pin 18 "fuel pump relay" (which is supposed to be a switched earth) on the r33 ecu nothing happens...we chucked the multimeter on it and got 4V for 5 seconds on accessories and then 0 untill the motor was cranked and get another 4V again. This seems the reverse of what i want??? as the ecu should earth ignition power through the relay into pin 18 not provide it... but we also realised that our relay needs 10v minimum to close so with a really expensive relay that trips on 4v and can hold the amps of the fuel pump we wired pin 18 in as the hot side of the relay switch and earthed the other side to the body. On first test The multi meter shows a 4V for 5 seconds on accessories as the fuel pump primes then off then 4v on again when cranking, from here the car fires up as normal and will continue to run and is quite drivable. However this is when the real problem starts. turn the car off. pin 18 provides a constant 4V's keeping the fuel pump running for well over 1min (didn't dare let it run any longer) to turn the pump off you have to turn the keys to accessories again and in 5 seconds the fuel pump shuts down as it would after priming the fuel rail and realizing the motor isn't turning. now there are probably a million simple ways to fix this however i want this to function as it should so that in the event of an accident my pump doesn't keep running after the engines stopped. i just need some help figuring out why my pin 18 puts out 4v's and does everyone else's r33 rb25 ecu do that? and is there pin 18 actually a switched earth? (noob question, what is the best way to tell a switched earth?) and what tells the ecu that the motors running and what tells it when its stopped? any help at all would be greatly appreciated. Thanks Steven. pic http://www.skylinesaustralia.com/forums/post-a255674-